package com.hmdp.utils;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.util.StrUtil;
import com.hmdp.dto.UserDTO;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Map;
import java.util.concurrent.TimeUnit;

public class RefreshTokenInterceptor implements HandlerInterceptor {

    //注入Redis
    private StringRedisTemplate stringRedisTemplate;

    public RefreshTokenInterceptor(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    //Controller前的操作拦截
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {


        //获取请求头中的token
        String token=request.getHeader("authorization");

        if(StrUtil.isBlank(token))
        {
            //不存在，拦截返回401状态码
            response.setStatus(401);

            return false;

        }

        //基于token获取redis中的用户
        Map<Object, Object> userMap = stringRedisTemplate.opsForHash().entries(RedisConstants.LOGIN_USER_KEY+token);

        //判断用户是否存在
        if(userMap.isEmpty())
        {
            //不存在，拦截
            response.setStatus(401);
            return false;
        }

        //将查询到的hash数据转为UserDTO对象
        UserDTO userDTO = BeanUtil.fillBeanWithMap(userMap, new UserDTO(), false);


        //存在。保存用户信息到ThreadLocal

        UserHolder.saveUser(userDTO);

        //刷新token的有效期
        stringRedisTemplate.expire(RedisConstants.LOGIN_USER_KEY+token,RedisConstants.LOGIN_USER_TTL, TimeUnit.MINUTES);

        //放行
        return true;
    }

    //业务执行完毕销毁用户信息，防止内存泄露
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

        //移除用户(本线程)
        UserHolder.removeUser();


    }
}
